Implement config CLI MVP

app/ghcup-gen/Validate.hs

@@ -237,7 +237,7 @@ validateTarballs (TarballFilter etool versionRegex) dls gt = do
                   ($(logError) $ T.pack $ prettyShow e)
                 liftIO $ exitWith (ExitFailure 2)
 
-    let appstate = AppState (Settings True False Never Curl True GHCupURL False) dirs defaultKeyBindings (GHCupInfo mempty mempty mempty) pfreq
+    let appstate = AppState (Settings True False Never Curl False GHCupURL False) dirs defaultKeyBindings (GHCupInfo mempty mempty mempty) pfreq
 
     r <-
       runLogger

app/ghcup/Main.hs

@@ -78,6 +78,8 @@ import qualified Data.Map.Strict               as M
 import qualified Data.Text                     as T
 import qualified Data.Text.IO                  as T
 import qualified Data.Text.Encoding            as E
+import qualified Data.Yaml                     as Y
+import qualified Data.Yaml.Pretty              as YP
 import qualified Text.Megaparsec               as MP
 import qualified Text.Megaparsec.Char          as MPC
 
@@ -105,6 +107,7 @@ data Command
   | Rm (Either RmCommand RmOptions)
   | DInfo
   | Compile CompileCommand
+  | Config ConfigCommand
   | Whereis WhereisOptions WhereisCommand
   | Upgrade UpgradeOpts Bool
   | ToolRequirements
@@ -173,6 +176,8 @@ data RmOptions = RmOptions
 
 data CompileCommand = CompileGHC GHCCompileOptions
 
+data ConfigCommand = ShowConfig | SetConfig String String | InitConfig
+
 data GHCCompileOptions = GHCCompileOptions
   { targetGhc    :: Either Version GitBranch
   , bootstrapGhc :: Either Version FilePath
@@ -408,6 +413,12 @@ com =
                   <> footerDoc (Just $ text changeLogFooter)
                   )
                )
+          <> command
+               "config"
+               (   Config
+               <$> info (configP <**> helper)
+                        (progDesc "Show or set config" <> footerDoc (Just $ text configFooter))
+               )
           <> commandGroup "Other commands:"
           <> hidden
           )
@@ -482,6 +493,17 @@ Examples:
   ghcup prefetch ghc 8.10.5
   ghcup --offline install ghc 8.10.5|]
 
+configFooter :: String
+configFooter = [s|Examples:
+
+# show current config
+ghcup config
+
+# initialize config
+ghcup config init
+
+# set <key> <value> configuration pair
+ghcup config <key> <value>|]
 
 installCabalFooter :: String
 installCabalFooter = [s|Discussion:
@@ -786,6 +808,19 @@ Examples:
   # build cross compiler
   ghcup compile ghc -j 4 -v 8.4.2 -b 8.2.2 -x armv7-unknown-linux-gnueabihf --config $(pwd)/build.mk -- --enable-unregisterised|]
 
+configP :: Parser ConfigCommand
+configP = subparser
+      (  command "init" initP
+      <> command "set"  setP -- [set] KEY VALUE at help lhs
+      <> command "show" showP
+      )
+    <|> argsP -- add show for a single option
+    <|> pure ShowConfig
+ where
+  initP = info (pure InitConfig) (progDesc "Write default config to ~/.ghcup/config.yaml")
+  showP = info (pure ShowConfig) (progDesc "Show current config (default)")
+  setP  = info argsP (progDesc "Set config KEY to VALUE")
+  argsP = SetConfig <$> argument str (metavar "KEY") <*> argument str (metavar "VALUE")
 
 whereisP :: Parser WhereisCommand
 whereisP = subparser
@@ -1258,6 +1293,27 @@ toSettings options = do
          , bShowAllTools = fromMaybe bShowAllTools kShowAllTools
          }
 
+updateSettings :: UTF8.ByteString -> Settings -> IO Settings
+updateSettings config settings = do
+  settings' <- runE @'[JSONError] $ lE' JSONDecodeError . first show . Y.decodeEither' $ config
+
+  case settings' of
+    VRight r -> pure $ mergeConf r settings
+    VLeft (V (JSONDecodeError e)) -> do
+      B.hPut stderr ("Error decoding config: " <> (E.encodeUtf8 . T.pack . show $ e))
+      die ""
+    _ -> die "Unexpected error!"
+  where
+   mergeConf :: UserSettings -> Settings -> Settings
+   mergeConf UserSettings{..} Settings{..} =
+     let cache'      = fromMaybe cache uCache
+         noVerify'   = fromMaybe noVerify uNoVerify
+         keepDirs'   = fromMaybe keepDirs uKeepDirs
+         downloader' = fromMaybe downloader uDownloader
+         verbose'    = fromMaybe verbose uVerbose
+         urlSource'  = fromMaybe urlSource uUrlSource
+         noNetwork'  = fromMaybe noNetwork uNoNetwork
+     in Settings cache' noVerify' keepDirs' downloader' verbose' urlSource' noNetwork'
 
 upgradeOptsP :: Parser UpgradeOpts
 upgradeOptsP =
@@ -1292,6 +1348,12 @@ describe_result = $( LitE . StringL <$>
                      )
                    )
 
+formatConfig :: Settings -> KeyBindings -> String
+formatConfig settings keybindings = unlines [formatSettings, formatKeybindings]
+ where
+  formatKeybindings = unlines . ("key-bindings:":) . map ("  "++) . lines . UTF8.toString . YP.encodePretty yamlConfig $ keybindings
+  formatSettings = UTF8.toString . YP.encodePretty yamlConfig $ settings
+  yamlConfig = YP.setConfCompare compare YP.defConfig
 
 main :: IO ()
 main = do
@@ -1990,6 +2052,28 @@ Make sure to clean up #{tmpdir} afterwards.|])
                         runLogger $ $(logError) $ T.pack $ prettyShow e
                         pure $ ExitFailure 9
 
+            Config InitConfig -> do
+              path <- getConfigFilePath
+              writeFile path $ formatConfig settings keybindings
+              runLogger $ $(logDebug) [i|"config.yaml initialized at #{path}|]
+              pure ExitSuccess
+
+            Config ShowConfig -> do
+              putStrLn $ formatConfig settings keybindings
+              pure ExitSuccess
+
+            Config (SetConfig k v) -> do
+              case v of
+                "" -> die "Empty values are not allowed."
+                _  -> do
+                  settings' <- updateSettings [i|#{k}: #{v}\n|] settings
+                  runLogger $ $(logDebug) $ T.pack $ show settings'
+
+                  path <- getConfigFilePath
+                  writeFile path $ formatConfig settings' keybindings
+
+                  pure ExitSuccess
+
             Whereis WhereisOptions{..} (WhereisTool tool (Just (ToolVersion v))) ->
               runLeanWhereIs (do
                 loc <- liftE $ whereIsTool tool v

ghcup.cabal

@@ -226,6 +226,7 @@ executable ghcup
     , uri-bytestring        ^>=0.3.2.2
     , utf8-string           ^>=1.0
     , versions              >=4.0.1    && <5.1
+    , yaml                  ^>=0.11.4.0
 
   if flag(internal-downloader)
     cpp-options: -DINTERNAL_DOWNLOADER

lib/GHCup/Download.hs

@@ -320,12 +320,11 @@ download uri eDigest dest mfn etags
     -- destination dir must exist
     liftIO $ createDirRecursive' dest
     let fromFile = T.unpack . decUTF8Safe $ path
-    destFile <- liftE . reThrowAll @_ @_ @'[DownloadFailed] DownloadFailed $ getDestFile
     liftIO $ copyFile fromFile destFile
     pure destFile
   dl = do
-    destFile <- liftE . reThrowAll @_ @_ @'[DownloadFailed] DownloadFailed $ getDestFile
+    let uri' = decUTF8Safe (serializeURIRef' uri)
-    lift $ $(logInfo) [i|downloading: #{uri'} as file #{destFile}|]
+    lift $ $(logInfo) [i|downloading: #{uri'}|]
 
     -- destination dir must exist
     liftIO $ createDirRecursive' dest
@@ -367,7 +366,7 @@ download uri eDigest dest mfn etags
                             _ -> liftE $ throwE @_ @'[DownloadFailed] (DownloadFailed (toVariantAt @0 (MalformedHeaders headers)
                               :: V '[MalformedHeaders]))
 
-                          writeEtags destFile (parseEtags headers)
+                          writeEtags (parseEtags headers)
                     else
                       liftE $ lEM @_ @'[ProcessError] $ exec "curl" 
                         (o' ++ ["-fL", "-o", destFile, T.unpack uri']) Nothing Nothing
@@ -384,13 +383,13 @@ download uri eDigest dest mfn etags
                         case _exitCode of
                           ExitSuccess -> do
                             liftIO $ copyFile destFileTemp destFile
-                            writeEtags destFile (parseEtags (decUTF8Safe' _stdErr))
+                            writeEtags (parseEtags (decUTF8Safe' _stdErr))
                           ExitFailure i'
                             | i' == 8
                             , Just _ <- find (T.pack "304 Not Modified" `T.isInfixOf`) . T.lines . decUTF8Safe' $ _stdErr
                                      -> do
                                           $logDebug "Not modified, skipping download"
-                                          writeEtags destFile (parseEtags (decUTF8Safe' _stdErr))
+                                          writeEtags (parseEtags (decUTF8Safe' _stdErr))
                             | otherwise -> throwE (NonZeroExit i' "wget" opts)
                       else do
                         let opts = o' ++ ["-O", destFileTemp , T.unpack uri']
@@ -405,10 +404,10 @@ download uri eDigest dest mfn etags
                       let addHeaders = maybe mempty (\etag -> M.fromList [ (mk . E.encodeUtf8 . T.pack $ "If-None-Match"
                                                                          , E.encodeUtf8 etag)]) metag
                       liftE
-                        $ catchE @HTTPNotModified @'[DownloadFailed] @'[] (\(HTTPNotModified etag) -> lift $ writeEtags destFile (pure $ Just etag))
+                        $ catchE @HTTPNotModified @'[DownloadFailed] @'[] (\(HTTPNotModified etag) -> lift $ writeEtags (pure $ Just etag))
                         $ do
                           r <- downloadToFile https host fullPath port destFile addHeaders
-                          writeEtags destFile (pure $ decUTF8Safe <$> getHeader r "etag")
+                          writeEtags (pure $ decUTF8Safe <$> getHeader r "etag")
                     else void $ liftE $ catchE @HTTPNotModified
                                         @'[DownloadFailed]
                                    (\e@(HTTPNotModified _) ->
@@ -421,18 +420,12 @@ download uri eDigest dest mfn etags
 
 
   -- Manage to find a file we can write the body into.
-  getDestFile :: Monad m => Excepts '[NoUrlBase] m FilePath
+  destFile :: FilePath
-  getDestFile = 
+  destFile = maybe (dest </> T.unpack (decUTF8Safe (urlBaseName path)))
-    case mfn of
+                  (dest </>)
-        Just fn -> pure (dest </> fn)
+                  mfn
-        Nothing
-          | let urlBase = T.unpack (decUTF8Safe (urlBaseName path))
-          , not (null urlBase) -> pure (dest </> urlBase)
-          -- TODO: remove this once we use hpath again
-          | otherwise -> throwE $ NoUrlBase uri'
 
   path = view pathL' uri
-  uri' = decUTF8Safe (serializeURIRef' uri)
 
   parseEtags :: (MonadLogger m, MonadIO m, MonadThrow m) => T.Text -> m (Maybe T.Text)
   parseEtags stderr = do
@@ -451,8 +444,8 @@ download uri eDigest dest mfn etags
         $logDebug "No etags header found"
         pure Nothing
 
-  writeEtags :: (MonadLogger m, MonadIO m, MonadThrow m) => FilePath -> m (Maybe T.Text) -> m ()
+  writeEtags :: (MonadLogger m, MonadIO m, MonadThrow m) => m (Maybe T.Text) -> m ()
-  writeEtags destFile getTags = do
+  writeEtags getTags = do
     getTags >>= \case
       Just t -> do
         $logDebug [i|Writing etagsFile #{(etagsFile destFile)}|]

lib/GHCup/Errors.hs

@@ -327,15 +327,6 @@ instance Pretty UnexpectedListLength where
 
 instance Exception UnexpectedListLength
 
-data NoUrlBase = NoUrlBase Text
-  deriving Show
-
-instance Pretty NoUrlBase where
-  pPrint (NoUrlBase url) =
-    text [i|Couldn't get a base filename from url #{url}|]
-
-instance Exception NoUrlBase
-
 
 
     ------------------------

lib/GHCup/Types/JSON.hs

@@ -316,3 +316,6 @@ deriveJSON defaultOptions { sumEncoding = ObjectWithSingleField } ''URLSource
 deriveJSON defaultOptions { sumEncoding = ObjectWithSingleField } ''Key
 deriveJSON defaultOptions { fieldLabelModifier = \str' -> maybe str' T.unpack . T.stripPrefix (T.pack "k-") . T.pack . kebab $ str' } ''UserKeyBindings
 deriveJSON defaultOptions { fieldLabelModifier = \str' -> maybe str' T.unpack . T.stripPrefix (T.pack "u-") . T.pack . kebab $ str' } ''UserSettings
+
+deriveToJSON defaultOptions { fieldLabelModifier = kebab } ''Settings
+deriveToJSON defaultOptions { fieldLabelModifier = drop 2 . kebab } ''KeyBindings -- move under key-bindings key